4 large potatoes, sliced 1/4" thick Olive oil, salt and pepper
1 tsp. dry mustard 1 1/2 Tbs. sugar 1/2 tsp salt 2 Tbs. flour 1/4 tsp. paprika 1 tsp. celery seed 1/2 cup cold water 2 egg yolks 1/4 cup vinegar 2 oz. Original Zip-It 1/4 cup sour cream
Parboil potato slices for 10 minutes. Pat potato slices dry, brush with olive oil and season with salt and pepper. Grill potatoes until browned. Mix together the mustard, sugar, salt, flour, paprika and celery seed. Beat in the top of a double boiler the cold water, yolks and vinegar. Stir in the seasoning flour mixture. Continue stirring over boiling water until thick and smooth, remove from heat. Stir in the Zip-It and sour cream. Serve warm or chilled on grilled potato slices.